<template>
  <div class="flow-menu" ref="tool">
    <div v-for="menu  in  menuList" :key="menu.id">
      <span class="ef-node-pmenu" @click="menu.open = !menu.open">
        <i :class="{'el-icon-caret-bottom': menu.open,'el-icon-caret-right': !menu.open}"></i>
        &nbsp;{{menu.name}}
      </span>
      <ul v-show="menu.open" class="ef-node-menu-ul">
        <draggable @end="end" @start="move" v-model="menu.children" :options="draggableOptions">
          <li
            v-for="subMenu in menu.children"
            class="ef-node-menu-li"
            :key="subMenu.id"
            :type="subMenu.type"
          >
            <i :class="subMenu.ico"></i>
            {{subMenu.name}}
          </li>
        </draggable>
      </ul>
    </div>
  </div>
</template>
<script>
import draggable from "vuedraggable";

var mousePosition = {
  left: -1,
  top: -1
};

export default {
  data() {
    return {
      activeNames: "1",
      // draggable配置参数参考 https://www.cnblogs.com/weixin186/p/10108679.html
      draggableOptions: {
        preventOnFilter: false,
        sort: false,
        disabled: false,
        ghostClass: "tt",
        // 不使用H5原生的配置
        forceFallback: true
        // 拖拽的时候样式
        // fallbackClass: 'flow-node-draggable'
      },
      // 默认打开的左侧菜单的id
      defaultOpeneds: ["1", "2"],
      menuList: [
        // 0-开始节点；1-分支节点；2-审批节点；3-流程节点；
        {
          id: "1",
          type: "group",
          name: "节点添加",
          ico: "el-icon-video-play",
          open: true,
          children: [
            // {
            //   id: "12",
            //   type: "task",
            //   nodeType: 2,
            //   name: "分支节点",
            //   allshow: true,
            //   alledit: false,
            //   ico: "el-icon-odometer",
            //   // 自定义覆盖样式
            //   style: {},
            //   fildList: []
            // },
            {
              id: "13",
              type: "over",
              nodeType: 2,
              name: "审批节点",
              ico: "el-icon-goods",
              // 自定义覆盖样式
              style: {},
              fildList: []
            },
            // {
            //   id: "14",
            //   type: "end",
            //   nodeType: 2,
            //   name: "流程节点",
            //   ico: "el-icon-caret-right",
            //   // 自定义覆盖样式
            //   style: {},
            //   fildList: []
            // }
          ]
        }
        // {
        //     id: '2',
        //     type: 'group',
        //     name: '结束节点',
        //     ico: 'el-icon-video-pause',
        //     open: true,
        //     children: [
        //         {
        //             id: '21',
        //             type: 'end',
        //             name: '流程结束',
        //             ico: 'el-icon-caret-right',
        //             // 自定义覆盖样式
        //             style: {}
        //         }, {
        //             id: '22',
        //             type: 'over',
        //             name: '数据清理',
        //             ico: 'el-icon-shopping-cart-full',
        //             // 自定义覆盖样式
        //             style: {}
        //         }
        //     ]
        // }
      ],
      nodeMenu: {}
    };
  },
  components: {
    draggable
  },
  created() {
    /**
     * 以下是为了解决在火狐浏览器上推拽时弹出tab页到搜索问题
     * @param event
     */
    if (this.isFirefox()) {
      document.body.ondrop = function(event) {
        // 解决火狐浏览器无法获取鼠标拖拽结束的坐标问题
        mousePosition.left = event.layerX;
        mousePosition.top = event.clientY - 50;
        event.preventDefault();
        event.stopPropagation();
      };
    }
  },
  methods: {
    // 根据类型获取左侧菜单对象
    getMenuByType(type) {
      for (let i = 0; i < this.menuList.length; i++) {
        let children = this.menuList[i].children;
        for (let j = 0; j < children.length; j++) {
          if (children[j].type === type) {
            return children[j];
          }
        }
      }
    },
    // 拖拽开始时触发
    move(evt, a, b, c) {
      var type = evt.item.attributes.type.nodeValue;
      this.nodeMenu = this.getMenuByType(type);
    },
    // 拖拽结束时触发
    end(evt, e) {
      this.$emit("addNode", evt, this.nodeMenu, mousePosition);
    },
    // 是否是火狐浏览器
    isFirefox() {
      var userAgent = navigator.userAgent;
      if (userAgent.indexOf("Firefox") > -1) {
        return true;
      }
      return false;
    }
  }
};
</script>
